Web browsers are an integral part of the internet. Web browsers access information from web servers, and present the information to users in a convenient, easily understood manner.
How a web browser interacts with, and receives data from, web servers depends upon a number of parameters. A first type of parameters may be user selectable from a preferences or options menu of the web browser. These parameters include security preferences, javascript preferences, popup blocking preferences, web viewing preferences, and so on. For each of these parameters, a user can select a specific option (e.g., enable, disable, etc.).
A second type of parameters is a set of data structures that define a user identifying state. Examples of such data structures include a browser history, a browser cache, one or more cookies, etc. Cookies may be the only stateful mechanisms by which a server can store a session state on the browser. Conventional cookies apply to all browser instances.